Slower, harder hitting guns are better in almost every situation. Playing Peek-a-boo over a hill/around a building gives you a huge advantage over someone with a faster loading/lower damage gun as you can just sit back and only come out when you have loaded your shell.

It really depends on play style, but I would say most people look for:

1 - A balance of Damage/Penetration/ROF (88 short and long)
2 - As much damages as they can get their hands on, forget Penetration/ROF (the 152 derp cannon on the KV)
3 - And a few go for High Penetration/ROF with low damage (majority of lower tier guns)

Angry Fetus, thats a very big generalization. Because you are assuming two things with Peekaboo.

1) I don't just charge you, wich is a valid responce.

2) I don't have aim already set at your front drive sproket when you start to peek out, so I can easily track you, do some damage, and then when you get your track back on, you have the option of continuing to roll forward for your shot, with me nearing a second shot off before you can get back into cover. Or just retreating back into cover with no gain.

Generally speaking, it's really within the game at least, personal preference. I tend to prefer my german quick reloads. But there are plenty of times when I know I am only going to get one shot, and I'd like some more damage. But on the other hand I am sure there are a few russkie tank players out there facing down a group of meds wishing they had my RoF at the same time so.

I usually go for the gun with the best penetration. But assuming penetration values are roughly the same, my bias is towards the faster guns. However, I truely feel it all boils down to personal preference, as both types of guns have their advantages and disadvantages - I've experienced it both ways with a T-34's 57mm gun (30 rounds per minute with 85 damage per shot) and a KV's 152mm gun (2.7 rounds per minute with 910 damage per shot). But the reason I'm biased towards the faster guns is because of all the times I've had to slug it out toe-to-toe with another tank, I've managed to keep their tank constantly rocking enough that it screws up their own shot. Either that or I've done so much component damage with all the shells I've put into them that the odds quickly shift against them, especially if I managed to take out the gunner or even the gun itself. Granted the slower guns have the potential of 1 or 2 shotting an opponent so they never even get the chance to shoot back, but the slower guns usually have lousy accuracy at the longer ranges, and whenever I miss at any range with a slow gun it's horrendously painful to try to get away from the bad guys as they unload shot after shot after shot into me instead of fighting back and doing what damage I can. The faster guns usually have the additional benefit of also being more accurate, increasing their overall utility making them useful in more situations.

Angry Fetus, thats a very big generalization. Because you are assuming two things with Peekaboo.

1) I don't just charge you, wich is a valid responce.

2) I don't have aim already set at your front drive sproket when you start to peek out, so I can easily track you, do some damage, and then when you get your track back on, you have the option of continuing to roll forward for your shot, with me nearing a second shot off before you can get back into cover. Or just retreating back into cover with no gain.

There's a reason I said "almost every situation"

1) That's why a smart player keeps a gap between them and the enemy. Even if you charge, that doesn't necessarily give you the advantage. You're assuming I'm alone.

2) Again, a smart player will take a corner at an angle (greatly increasing the chance of a ricochet), therefore only exposing their track once their gun can also aim around the corner. That argument is not valid.

Sure you can say it's a personal preference. But at a competitive level, you can abuse your RoF with calculated gameplay.

Assuming equal penetration, I'd rather have the slow gun most of the time. Its easier to mitigate the issues vs other heavies. Vs medium I'd rather have the ROF so I can keep 'em tracked. Either way, penetration is king. I'd rather pen every time than have a 50% chance of rounds bouncing off.